Tremolo still Ticking

[JustMike]

I rebuilt this heavily modded Super reverb and it's working, but the tremolo is still ticking. It starts somewhat loud and quiets down, but it's still there. I added the .01 cap per Fender bulletin #9. It has shielded leads from the intensity pot and I tried chopsticking the leads to no avail. Any ideas?

[tubenit]

Since it's a "heavily modded" Super Reverb,  ……………. could you share a schematic, please so that we can be a better help to you?    There may be something in your mods that plays a factor in the tremolo and we have no idea what the mods are?

A schematic and posted voltages would probably help.

With respect, Tubenit

[sluckey]

Look at the second pic on this page. Could be your problem...

     http://www.timeelect.com/jbl-twin.htm

[JustMike]

Sluckey, I lifted the components to no avail. FYI, the ticking only appears when the tremolo intensity is above 7. Maybe this is normal?


Tubenit, I've attached the layout I built to.
 Work I did;
 There was what I believe to be a channel switching relay with a 9v battery hanging below the chassis (yes). It had a 1/4" jack thru the front of the chassis where the normal channel bright switch was. This was taken out, rewired and a new bright switch was installed. This now works as it should.
 All electrolytics have been replaced as have the dog house dropping resistors per the attached layout.
 All bypass & coupling caps have been replaced.
 Tremolo pots were wired as PI master volume ckt (it looked like) tremolo circuit was gutted, rebuilt as shown on the attached layout.
 Bias ckt rebuilt per layout.
 6l6's replaced and rebiased to about 32mv across new 1 ohm cathode resistors.

[Leevi]

Replace the oscillator cathode resistor and cap with a led.
This is more a work around than solution.


http://www.valvewizard.co.uk/trem1.html


/Leevi

[Bieworm]

The ticking often occurs when the roach is not set up properly. Meaning, the distance of the neon  light bulb isn't set right towards the photocell. Sometimes pulling or pushing the neon bulb solves the problem.
Anyway, I modded my vibro king to bias vary trem. Muuuuuch better trem than the optotrem!!!

[Williamblake]

What about a 0.1u or smaller 300V cap from oscillator plate to ground? But maybe this just results in the intensity being lowered permanently.

[trobbins]

The tick relates to the neon striking, and one issue can be when a capacitance coupled pulse transfers to the intensity wiper, especially when the wiper is a higher impedance node (eg. wiper above 7). 

One technique to alleviate that transfer was to insert some grounded fine metal mesh between the neon and the LDR.  Not so easy with a pre-made roach, but it could be worthwhile trying to wrap some foil around the roach and connect it to the ground end of the LDR.  Another option to try could be to bypass the LDR with a capacitor (trial and error on value).  Another option is to shield the LDR lead over to the wiper, and back again from the top of the pot.

[mat janssen]

try to connect a 10Mohm resistor from point 6 of the tremolo oscillator (V5) to the nearest gnd. It helped me!

[Bieworm]

I previously had succes with a selfmade roach with an LDR and a red LED. It gives a rounder sinewave that trends to sound more like bias vary trem. Works like a charm. Total cost is less than a $ and some elbow grease. Required parts: 1 red LED, 1 LDR and 1" of heatshrink.  You can use other LED's too, but the red one seems to work out best. Buy a few LED's just in case you connect it reversedly.. it's immediately defect then. But when connected correctly it's rock solid.
But I never liked optotrem anyway, so I converted the trem circuit to bias vary trem on the 6L6's . Now THAT is tremolo!!!

[JustMike]

I replaced the blue wire connecting the speed pot to one of the oscillator caps with a shielded wire and I redressed the existing shielded wires going to the intensity pot. Seems to have fixed the problem.

[smilan]

Look at the second pic on this page. Could be your problem...

     http://www.timeelect.com/jbl-twin.htm

After trying all the regular fixes (0.01 cap from the 10M resistor to ground, disconnecting the leg of the 100K resistor on the 'Speed' pot from the chassis and connect it directly to the 2K7 cathode resistor in the phase-shift oscillator, replacing the cathode resistor with a LED.
what have stopped the ticking was to hanging the parts in the air as described at the second pic on the link.